Ring fracturing machine



P. MITCHELL RING FRAQTURING MACHINE Aug. 30, 1932.

Filed Sept. 29, 1930 2 Sheets-Sheet 1 Aug- 1932- P. MITCHELL 1,374,786

RING FRACTURING MACHINE Filed Sept". 29, 19-50 2 Sheets-Sheet 2 W M HMW.

IN V ENTOR PETER MITCH ELL 7 ATTORNEY v Patented Aug. 30, 1932 PETERMITCHELL, on WINNIPEG, MANITO A, camera RING FRAo'rr'mIivG' MACHINEApplication filed september 29, 1930. Serial No. 485,289. i

The invention relates toimprovements in ring fracturing machines andparticularly to a machine for fracturing piston rings such as are usedon locomotive and such line type '5 engines and an object of theinvention is to provide a machine whereby a precast metal ring such asof cast ironcan be accurately,

easily and quickly transversely fractured to 1 divide the ring into anumber. ofsegment's and which after fracturing and upon slight grindingcan be re-assembled and used on the piston in the usual manner. a e

A further object is to construct the machine in a simple, durable andinexpensive manner and so that rings of various size can be easilyand-accurately set in place for fracturing and after having been set canbe clamped so thatthey are held during the interval that they are beingfractured and further, to provide tools associated with the machinewhich can be easily set in regard to the ring to be fractured,thepositioning of the tools being such that all segments will be of thesamelength and interchangeable and that the segments ofa plurality ofsimilar fractured rings will be the same. i

A further object is to'embody as part of the device, one or more aircylinders for effectively clamping the rings in pl'ace,'the air cylinderor cylinders being directly under the control of the operator.

A further object is to construct the machine so'that rings of varyingthickness may be clamped therein for fracturing purposes.

With the above more important and other minor objects in view which willbecome more apparent as the description proceeds, the'i-nventionconsists essentially in the arrangement and construction of partshereinafter more particularly described, reference being had to theaccompanyinig drawings, in which F l'is a side view of the complete machine. 7

Figure 2'is a plan view, part of the upper clamping plate being brokenaway to expose construction. f

Figure 3 is an enlarged detailed vertical sectional view at 33 FigureQ,certain parts 50 being shown in side elevation.

Figure 4 is a verticalsectional viewfa'l 4- l--Figure 2. i i a Figure 5is an enlarged detailed-vertical sectional View at 5 5 F igure-2. I

Figure 6 is an enlarged detailed' vertical sectional View at 6-(3 Figure2. a I Figure is a fragmentary view partly in side elevation and partlyin-vertical section showing certain modifications.

In the drawings like characters of refer- 0 ence indicate correspondingparts in the several' figures. I

a I might initially explain that at the .pres: ent time, piston ringsare being used in 'locomotive engines, the" rings being circular andformed from a plurality of segments. These rings are made from cast'ironand acc0rd mg to the presentpractice'theringis cast and has on suchaccount a fixed internal and external radius. Afterthe ring is cast,it'is I cut by a saw blade at intervals to provide the required number,of ring segmentswhich segments at the present time are all numbered asit is found that they are notinterchangeable; 5 r

'By so cutting the ring into segments by a saw blade, there is aninaccuracy occurring. in the fit of the assembled ring segments due tothe removal of the m'etal i cut I by the saw. Obviously if the saw cutsegments be re-assembled with theirends butted, they will not have acommon centre pointand on the other hand, if they bare-assembled with acommon centre point, there will be escape passages betwee'n the ends ofthe ring-segments; According to my invention, I have devised a machineby the use of which the'ring'can be transverselyfractured at desiredpoints,

thereby avoiding the loss0f=metal as occurs in saw cutting andaccordingly, therelis virtually no loss of material; so that'the ringsegments obtained fit accurately.

' Referring first to the constructionshown 'in Figs. 1 016 inclusive,a'suitable base or 5 bed 1 is provided a-nd'on this I mount in any 1 5 isuitable manner a bottom plate 2 herein "shown as circular, above whichI locate a circular topplate 3,-thetop' and bottom plates being hingedlyconnected-together as indi-' cate'd generally bythe referencenumeral forfracturing the cast iron piston rings of locomotive engines which arecircular.

V the edges 11. of the fulcrum members project vabove the horizontalplane containing the The bottom platevis provided in its top face withan annular channel 5 of predetermined width and depth and the base ofthe I channel is transverselyslotted 'in anumber ofplaces as indicatedat 6, the slots being positioned accurately so that they are all radialto the central axis of the annular -channel, that is, radial to thecentre point? Figure 2. The piston rings. as at present used are cut atthe present time into six segments and I accordingly provide the baseplate with twelve radial slots 6, all spaced accurately an equaldistance apart and one set. of six slotsbeing utilized to receive toolholders 8 and the other set ofsix slots receiving jam plates 9, the toolholders being alternated with the jam plates. It will be observed thatthe jamv plates have their up per faces extending slightly above thehorizontal plane containing the base of the channel (see Figure 4).

Eachftool h lder :crum member 10 inserted therein, said mem has ahardened steel fulher being provided with a V-shaped upper edge Q11.These fulcrum members .are

equally spaced and arranged with the edges ;11 extending radially withrespect to the centre point 7. It will also be observed that 1 "upperfaces of the jam plates 9.

.eter.

'The'width of the channel 5v is such that it will receive piston ringsof varying diam- Thepiston ring 12 to be fractured is "placed inahorizontal-position resting on .the blades of the cutters and iscentered accurately in regardv to the centre point 7.

The} ring herein shown is ofsuch a diameter that an outer centeringring'13 has been in- .serted, the ring 13 having itsouter edgeengaging-with the outer wall of the channel and its inner edge engagingwith the outer edge of the ring 12. If a larger ring than that 12were'placed in the machine, a smaller ring 13 would be used and if asmaller ring than that "12 were to be fractured in the machine,

a larger ring than that 13 would be used or 1 several rings such as that13.

The upper plate is provided with six similarslots'14 T'-shaped invertical cross section, the slots being radial to the centre point ofthe plate and being equi-spaced apart and being located such'that whenthe top plate is closed against the bottom plate, the latter slotsoverlie the cutters of the bottom plate.

the base ofthe chisel guide 15, 'thechisel Eachslot 14 receives slidablylamest guide being adjustably held in place by a bolt 16, the shank 17of which passes through the contracted or narrow portion of the slot 14and the head 18 of which is received in the lower or larger part of theslot. By releasing the nut 19 of the'bolt, one can shift the chiselguide in a direction radial to the L centre point of the plateand whenproperly v adjusted, can fasten it firmly by tightening up the nut andit is here pointed out that the under side of the guide is provided witha guiding extension or rib 20 slidably re ceiv'ed in the upper part ofthe slot 14.

The guide in each instance is vertically bored as indicated at 21 toreceive slidably a shank 22, the shank havingthe upper end thereofterminating in an enlarged head 23 and the lower end thereofsubstantially V- shaped in vertical cross section and carrying ahardened steel chisel or cutter 24 formed to the shape of the upper faceof the piston tion of the shank in the guide but permitting of the readyend-wise shifting movementof the shank. A coiled spring 27 interposedbetween the head 23 and'the guide,operates to hold the head andconsequently the cutter 2 1 in its upper position as best shown inFigures 3 and 4. Y

I wish it to be here distinctly understood that when the, top plate isclosed down tightly against the bottom plate, the cutting edges of thecutters 24 are vertically above the cutting edges of the cutters 10 andthat all cutters are radial to a vertical axis passing through thecentre point 7. "Obviouslythe cutters 24: will'be set so that whenthe-heads 23 are struck down as by a mallet or hammer, they will strikethe upper face of the inserted piston ring. V

The upper plate is provided with a handle 28 for manipulating purposesand suitable means is provided for clamping the top and bottom platestogether. In the present instance, I have fastened an air cylinder 29"toset in the position shown in the'drawings, is

free to escape through the slot 33- upon the top plate being raised. Ahandle 36 extends angularly outwardly from the head 35 and obviouslyafter one has closed theplate 3 together.

down against the plate 2, one can turn the handle in either directionsothat the head '35 will sit transversely of the slot 33. An air orother such pressure pipe 37 leads to the upper end of the cylinder andthe passage of air is controlled by a suitable two-way cock or valve 38.

Assuming the parts positioned as shown best in Figures 2 and 3 and thatit is desired and allows the work to be done very quickly and easily.

I have also considered it desirable to counterbalance the upper plate 3so that after it has been released by the clamping device,

it will have a natural tendency to rise in order to permit of'the readyinsertion of another ring. To this end, the top plate at the sideadjacent the hinges is provided with an extension or tail piece 39 towhich I fasten a weight or counter balance 40. V

In Figure 6, I have shown in dotted outline, the position occupied bythe head 35 and handle 36 when they have been turned 90.

I have hereinbefore remarked that this machine can be used to fracturepiston rings of different thickness and the machine herein shown willtake piston rings of two different thicknesses. This latter isaccomplished in the following manner.

The bottom plate is provided with a pair of extending bearing lugs 41and 42 and the top plate with a pair of extending bearing lugs 43 and 44and the lugs receive similar bolts 45 which hingedly connect the platesThe bolt in each'instance is fastened by a jam screw 46 to the lug 41 to'42 and has that part 45thereof whichis received within the lug 43 or 44eccentric as best shown in Figure 5. According to this arrangement, ifthe eccentric parts 45 of the bolts be ,set down, the top plate will beset as it should be when the machine is to receive the piston ring ofleast thickness, whereas, if the eccentric portion 45 be set up, themapiston ring of the greatest thickness. The setting of the bolts 45 isaccomplished by releasing the jam screws 46 and turning the bolts andthen tightening down the am screws.

WVhen it is desired to sever the ring, it is only necessary to place andcentre it in the channel 5 with the under side thereof resting on thecutters 10, all cutters having been pre viously properly set, then clampthe plates together in the manner described and then moval of the ring.chine will be set as it should be to receive the finally strike each ofthe heads- 23a sharp blow with a hammer or mallet to cause thetransverse fracturing of the rings at the 'desired points and into thedesired number of segments." Subsequentlythe' top plate is released "andswung up and'the segments are :remo'ved.- I V I have found that'afterthe ring has been fractured to form the segments that'it is onlynecessary to touch up the ends of the segments on an emery stone anditwill be found thatthey'are then all intercha-ngeable,"any six of whichcan be used to form the re-assem bled piston ring. 1 The re-assembledring will fit the cylinder very accurately. It'is to be particularlynoted thatiwhen the non-severed ring is clampedin the machine that thering istensioned by the clamping I over six transverselyextendingfulcrums, such fulcrums being the sharp edges ofthe cutters l0.Gonse'quently'when theitop face of the ring is struck successively siXsharp blows by the chisels." in: locationsdirectly above the fulcrumswhich are'the positions where the ring is in greatest tension, the saidring will fracture in definite directions which in the machine hereinshown are'radial to the centre point? s In the modified constructionshown in Fig. 7, it will be noted that'the upper plate 3 is mounted toslide vertically on suit-able guide rods 50. The lower ends of the guiderods are fastened to the bottom plate 2, while the- 7 upper ends of saidguide rods are attached to a frame 51 on which is mounted a cylinder 52.

This cylinder contains a'piston 53 connected by the piston rod 54 to thecentral portionof the top plate 3. The opposite-ends of the 'cylinder 52are connected by branch pipes 55 and 56 to a three way valve 57 whichinturn is connected to a supply pipe 58 leading to a suitable source offluid pressure (not shown). Through the medium'of the valve the fluidpressure may be selectively applied to opposite sides of the piston inthe customary manner. The application of fluid pressure to the upperside of the piston causes the top plate 3 to be forced downwardly to aring clamping position, while the application of fluid pressure to theunderside of said piston causes the top plate 3 to be raised to anelepermit placement or re-' vated position to As also shown to advantagein Fig. 7 each of the chisels carried by the top plate 3 may be equippedwith a pneumatic operating hammer 59 of any suitable construction. Eachhammer isprovid'ed with a fluid connection and the several hammers areadapted to be connected to a suitable source of fluid pres-..

sure in any suitable manner permitting simultaneous actuation of thehammer during the ring fracturing operation. i

Having thus described my invention, what I claim is:

I 1. Apparatus for fracturing a cast metal member comprising ahorizontal support presenting a plurality of spaced fulcrum edgesprojecting upwardly therefrom, said cast member being arranged with oneside engaging said fulcrum ed es, a plurality of guides extendingupwardly from said sup port, a clamping member slidably mounted on-'said guides and movable thereon to and from clamping engagement with theopposite side of the cast member, a cylinder and piston device formoving said clamping member, a plurality of movable cutters carriedbythe clamping member and adapted to engage the cast member at points inline with the ful-' crum edges and a pneumatic hammer associated witheach of said cutters.

2. Apparatus for fracturing a cast metal member comprising a horizontalsupport having a recess in its upper surface for receiving said member,a plurality of spaced fulcrum edges projecting upwardly from the bottomwall ofthe recess and engageable with one side of the cast member tosupport said member in a horizontal position, a clamping member mountedto move vertically into and out of clamping engagement with the upperside of the cast member, a cylinder mounted above the clamping member, apiston operating in the cylinder and connected to the clamping member toraise and lower the same with ref: erence to the support, a plurality ofmovable cutters carried by the clamping member and arrangedto be driveninto'fracturing engagement with the upper side of the cast member atpoints in line with said fulcrum edges and a pneumatic operating hammerassociated wlth each of said cutters.

' In witness whereof I have hereunto set my hand.

' PETER MITCHELL.

